thomson



(No Model.) 3 Sheets-Sheet 1.

E. THOMSON. I MEANS FOR PREVENTING ARCING IN ELECTRIC POWER STATIONS.

Patented June 5, 1894 (No Model.) 3 SheetsSheet 2.

B. THOMSON. MEANS FOR PREVENTING AROING IN ELEGTRIG POWER STATIONS.

Patented June 5, 1894.

SEE:

r I I l lllllllllllllll|||||||l|||ll|l4 (No Model.) 3 SheetsSheet 3.

- E. THOMSON. MEANS FOR PREVENTING ARGING IN ELEGTRIG POWER STATIONS.

Patented Jun 5, 1894:

EEIEEE WIT III II '1 UNITED STATES," BATE OF I E} 'ELIHU THOMSON, on S AMPseo'rtr, MASSACHU ETTS, ns'sreivon TO THE THOMSON-HOUSTON ELECTRIQOOMPANY, 0F OON W IQ Q MEANS FOR PREVENTINGARCING' m tltctmc-rowrn STAT-IONS.

SPECIFICATION forming part of Letters Patent No. 520,809, dated m. 5,1894} Q Application tiled September 1,

To all whomit may concerm Be it known that L'EL'IHU THOMSON, a citizen of the United States, residing at Swampscott, county of Essex, State of Massachusetts, have invented a certain new and useful Improvement in Means for Preventing Arcing 1n Electric-Power Stations, of which the following is a specification.

My invention comprises certain improvements designed to be used in connectionwith elcctrlc power installations in which are employed currents of electricity of great volume power stations, such as fuses, lightning arresters, and switches, to the end that'the air ot may dlsrupt any are whichm'ayform thereat, and the pipes lead'inglfrom the air reservoir to the circuit breaking apparatus are provided with valves 50 arrangedthat the get of air may be delivered upon the arcs at the moment the circuit is ruptured. Thus the safety .fuse may be madeto control a. valve in such manner that on blowing or melting the stream of air will be turned ,onand eXtinguishJanyarc at that point, and also the switches when thrown to open the line circuit -:may be made. to automatically openv valves whereby-the jet of air-Twill be thrown between the switch'co'ntacts.

"My present invention also provides means for getting rid of the fumesor gases arising from the arcs,'and to'that end'ylprovide'a separate, fume chamber distin'ctfrom the sta tion-proper, so-placed as to receive the jets. of air after they have been forced-through the arcing spaces. 1 z

My invention also comprises other features lowing descriptionand claims. In the accompanying drawings 'Figlrreil of construction as will 'be'see'n' from the fol 1899. stun No.363,679. (nominally I showsa stationswitch board having my im V provements applied thereto. Fig. 2 shows a plan of an electric power. station withce'rtain of the devices therein used. Fig. 3 is anenlarged view'of an arrangement of fuses after the manner of my invention. -Fig. 4 illustrates the fume chamber in section. "Fig. 5, illustrates a lightning'arrester arranged in accorda ce with my invention. -Fig. 6 'is'a valvesshowing also a preferred form of fuse for use inconnection therewith. Fig. 7 is an enlarged view of a modified form of vdevice and similar apparatus. In Fig. l, G, G, .G",are electric generators shown. ezgternal or line circuits on one side through ,S'-', fuses F, F, F", to the line a, and from the other side to the other line b and other a at W, W, which is employed in electric disrosters 'L, L, L-' a connection to earth E 1 is 1 from the machines in frointhe lines.

cuit breaking apparatus described which is breakingapparatus so that upon the. interconnected; by pipe Pf to the reservoir A, in

shown as consisting of a. main tube T,-T, and

sectiona view of the valve chamberandsuch. as generally will be used with switche lightningarres'ters L, L, L, switches S, S',

. tribution. systems. From the lightning-at 'In,order to avoid arcing'a't the variouscir f which the air is. compressed, the pressnreba' H ingindicated by a gageV in-the usual-man- .ner. From} the reservoir is ledta distributing systemof pipes or other ducts which are.

one or-a numbe suitably located in a station y 1 or power hous and coupled up to form a multiple-arc or series system or aeombina-- tionof the two, the first being he one herein" The generators are co nected to the,

station apparatus illustratedconventionally v:

used in such an installatioml provide an air. I I di tribution system (though other insulating fluids might be usedwith the same results)" 'which distributes air-tothe different'circuit, p a k '90 rnqtion oi thecircuit at any onethe :ai'r jet wil be present to extinguish any arcsforme d'. thereat. -,At the rightfwilltbe seen an ear pn' mp0, driven by an electricmotor M,-;and.

too 3 branch tubes't, t, t, extending to thecircuit interrupting-devices hercinhefore mentioned.

- ,3 ing ofthe circuit, so that the jet of airmay be discharged across the space where the arc is fornied. To this end I provide at the switches some such arrangementas is illustrated in Fig. 7, wheret represents the discharge tube, S the switch, and J' the nozzle opening from the valve chamber and pointing toward the switch terminals.

Without the valvechamber are two partitions Z, Z,

- having central openings which are closed al- '15 ternately by the valves V, V,.the arrangem'ent'being such'that the valve V is opened when the switch is thrown as shown at S, Fig. ;1, .and after a predetermined. interval which may beLregulated by a dash pot the so pipeis again closed as at S" by valve V.

In Fig. 6 another preferred arrangement of valves is illustrated, and also a fuse .for use therewith. The latter consists of two portions, a main fuse wire F, easily melted by an excessive current, and an auxiliary wire f which is small and of metal, such as steel, iron, German, silver, 820., having great tensional streiigth ascomp'a'red with the wire F. The Valve V is normally held closed against the air 3o pressure and the tension of spring s, which bears against theplunger head p, by the stem m which rests against wiref. When the main fuse wire F is melted the current is diverted to the wire f whioh'is instantly consumed.v 5 The valveV is automatically opened and the air blows out any are which may have formed between the terminals. To prolong the action of the air jet and so insure the extinguishing of the arc the movement of the valve is m- I acgtardedby the head 10, which allows air to pass slowly into the space occupied by the spring 8, thus acting as a dash pot.

Fig. 5 illustrates a simple arrangement for av lightning arrester used with the air supply system herein described. The chimney H ,is placed in front of the arrester plates and may lead to the external air or a specially constructed fume vault. A static discharge readily leaps the gap separating the arrester plates but the formationof an arc is prevented because the normal line potential is incapable of sustaining such an are against the disruptive action of the air jet which-is continually-being driven across the sparking gap.

reservoir A, and to this end I provide an au- -tomatic starting and stopping mechanism for the motor M, driving the pump 0. Connected to the boiler A is a valve or piston P, the head .of which is held against the air pressure by a spring'Q, and'the stem. extends outward engaging with the pivoted switch S ,.so that .the outward movement of 'the' rod opens the switch contacts at D,D'. Hence when the air pressure has reached a predetermined amount the motor M is stopped, and when the air-pressure has fallen so that the spring Q I preferto keep a constant pressure in the in its extreme open or closed position, and to a snap it to either side of a dead center. In

this way the switch is not afiected by the slight fluctuations of the piston P and the motor M is positively started and stopped, Whereas if some such device was not used there would tend to be a continuous making and breaking of ,contact at the switch accompaniedwith sparking.

In Fig. 2 a plan of a station fitted with my improvements is shown. Y, Y, are the walls of the station proper, and 11 indicates a small fume chamber'or vault adjacent thereto to receive the'metallic vapors arising from the arcs and blown fuses. Between the interior of the station and the vault-there are open ngs in the wall Y,atthe points where the various circuit breakingapparatus is located to which the air jetis applied. -G, G, G' ',are the electric generators from which are led to the switch board the usual connections as indicated in dotted lines. A is the reservoir for the compressed air and the pipe T distributes it to the circuit breaking apparatus in use. In Fig.3 it is shown that the openings in the wall Y instead of leading into a vault II as in Fig. 2 may open to the exterior of the station, but this arrangement is not so desirable. It will of course be understood that the specific apparatus described may be varied within wide limits without departing from my bread invention. 7 'By controlling the air supply as above described from the general electric circuit, as through :the electro-magnetid motor, an automatic adaptation of the air pressure tothe needs of the system is secured, as the sursupplying devices are stopped or started simultaneously with the generating apparatus or are dependent on the electrical condition of the system.

Iclaim'- 1. The combination in an electric power i'n- 'stallation ot the various circuit breaking apparatus as described, used inconnectlon'therewith, with an air or other insulating fluid distribution system, arranged to deliver a et of air or. like fluid across the arcing space at any desired or necessary one of the said circuit-breaking apparatus, and an electromagnetic device connected with the general electric circuit of the installation and a controlling means for supplying the insulating fluid and itself controlled by devices operated by the ressure in the air system, as and for the purposes set forth. I

2. The combination in an electric power installation, of the various circuit breaking apparatus as described used in connection therewith, with an air or other insulating fluid distribution system arranged to deliver a jet of air or like fluid across the arcing space at any desired or necessary one of the said circuit breaking apparatus, a pump for said distribution system, an electro-magnetic device connected with the general electric circuit of the installation and controlling the pump and itself controlled by devices operated by the pressure in the air system.

3. The combination with a reservoir, and an insulating-fluid distributing system leading to the various circuit breaking apparatus of an electric power installation, and designed to prevent arcingthereat by delivering a jet of air or like fluid across the arcing space, of a compressor forcing air into the reservoir, and a pressure Valve connected with the reservoir and controlling the compressor.

4. The combination with a reservoir, and an insulating fluid distributing system leading,

to the various circuit breaking apparatus of an electric power installation and designed to prevent arcing thereat by delivering a jet of air or like fluid across the arcing space, of

- a compressor forcing air into the reservoir and driven by an electric motor, a controller for thesaid motor, and a pressure valve connected with the reservoir and actuating the controller; 7

5. The combination with an air reservoir, and adistribution system for distributing jets of air to the various circuit breaking apparatus of an electric power installation, of a pump for forcing air into said reservoir, an electric motor driving the pump, a switch in the'motor circuit, a spring holding the same on either side of a dead center, and a device actuated by the air pressure in the reservoir connected to and automatically operating said switch as set forth.

6. The combination in an electric power installation,ofacircuitbreaker,withadischarge pipe through which air or other insulating .auxiliary wire as described.

air or other insulating fluid is delivered to prevent arcing at the circuit breaker, of a self-closing valve in the pipe held closed by the circuit breaker when the circuit is closed, but freed so as to temporarily open the valve when the circuit is broken, as described.

8. The combination witha fuse included in an electric circuit, of a discharge pipe for directing a blast of air across the arcing space 10. The combination with a circuit breaker in an electric power installation, and a discharge pipe through which air or other insulating fluid is forced to prevent arcing at the circuit breaker, of the valve automatically opened upon the breaking of the circuit, the

spring for closing the valve, and a dash pot for regulating the duration of the 'air blast as described. 7

11. The combination with a circuit breaking apparatusof a wall or partition on one side of said apparatus and provided with an opening in proximity thereto, and an'air or equivalent blast apparatus for propelling toward said opening any arc which may form at said circuit breaking apparatus.

12. The combination with a circuit breaking apparatus of a wall or partition on one side thereof, and provided with an opening in proximity thereto, and arc propelling means for forcing toward said opening any are that may form at said circuit breaking apparatus.

ELIHU THOMSON.

Witnesses:

JOHN W. GIBBONEY, ROBERT SHAND. 

